Structure of head in iron club for golf

ABSTRACT

To provide a structure of a head in an iron club for golf in which grass resistance at the time of shot can extensively be reduced, follow-through of swing of a club head can easily be conducted in the rough even by beginners and powerless golfers, poor shot (miss a shot) such as chip and shank can effectively be eliminated, and safety is ensured by solving the problem of accident resulting in injury and death by shank, etc. The structure of a head in an iron club for golf includes a grass relief groove  5  which is formed in a leading edge portion zone  4  of a club head 1 such that the grass relief groove  5  is open at a leading edge  4   a  and released at a surface  4   b  on the side of the striking face  2  of the leading edge portion zone  4  and at a surface  4   c  on the side of a sole face  3  of the leading edge portion zone  4.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to a structure of a head in an iron club for golf which can offer an effective follow-through of swing of a club head.

[0003] 2. Related Art

[0004] Shot using an iron club, especially shot from the rough involves various problems. Due to resistance of grass, follow-through of swing of the club head is difficult to be conducted in an ideal manner and the angle of the striking face is readily swayed thus greatly deviating the trajectory of the golf ball to right or left. It also results in poor shot (miss a shot) such as chip, shank, hook and the like, where the golfer cannot obtain an intended flight distance.

[0005] To make the golf ball escape from the rough of grass having a long height, the technique of skilled players is required. How to effectively make the golf ball escape from the rough is very important for improving the score. This is especially so for beginners and powerless golfers. In particular, shank raises such a serious problem that the caddy and galleries are likely to get injured. Moreover, the twisting of the club shaft due to grass resistance and impact resistance can cause the player to suffer from wrist pain.

SUMMARY OF THE INVENTION

[0006] It is, therefore, an object of a present invention to provide a structure of a head in an iron club for golf in which grass resistance at the time of shot can extensively be reduced, follow-through of swing of a club head can easily be conducted in the rough even by beginners and powerless golfers, poor shot (miss a shot) such as chip and shank can effectively be eliminated, and safety is ensured by solving the problem of accident resulting in injury and death by shank, etc.

[0007] To achieve the above object, according to the present invention, a structure of a head in an iron club for golf includes a grass relief groove which is formed in a leading edge portion zone of a club head such that the grass relief groove is open at a leading edge and released at a surface on the side of the striking face of the leading edge portion zone and at a surface on the side of a sole face of the leading edge portion zone. With this construction of the present invention, grass resistance at the time of shot, especially, grass resistance or soil resistance at the time of shot in the rough can be reduced by relieving grass or soil into the grass relief groove.

[0008] Moreover, a grass cutter for cutting grass introduced into the grass relief groove is formed with an edge of a wall for defining the glass relief groove. With this construction of the present invention, the reduction effect of grass resistance at the time of shot can be more improved by cutting grass while allowing the grass to escape into the grass relief groove.

[0009] Owing to the above-mentioned construction, follow-through of swing of a club head of an iron club can be conducted very easily, poor shot (miss a shot) such as chip and shank can effectively be eliminated, and the problem of accident resulting in injury and death by shank, etc can effectively be solved. In addition, the problem of injury of the player's wrist can be solved. Moreover, follow-through of swing at the time of duffing can be conducted in a satisfactory manner.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 shows a first example of an iron club, 1(A) is a plan view of a short iron club head with a striking face held in a generally horizontal posture, 1(B) is likewise a plan view with a sole face held generally in a horizontal posture, 1(C) is a sectional view taken on line A-A of 1(A) and 1(D) is an enlarged sectional view taken on line B-B of 1(A);

[0011]FIG. 2 shows a second example of an iron club, 2(A) is a plan view of a short iron club head with a striking face held in a generally horizontal posture, 2(B) is likewise a plan view with a sole face held generally in a horizontal posture, and 2(C) is a sectional view taken on line A-A of 2(A);

[0012]FIG. 3 shows a third example of an iron club, 3(A) is a plan view of a short iron club head with a striking face held in a generally horizontal posture, 3(B) is likewise a plan view with a sole face held generally in a horizontal posture, and 3(C) is a sectional view taken on line A-A of 3(A);

[0013]FIG. 4 shows a fourth example of an iron club, 4(A) is a plan view of a short iron club head with a striking face held in a generally horizontal posture, 4(B) is likewise a plan view with a sole face held generally in a horizontal posture, and 4(C) is a sectional view taken on line A-A of 4(A);

[0014]FIG. 5 shows a fifth example of an iron club, 5(A) is a plan view of a short iron club head with a striking face held in a generally horizontal posture, 5(B) is likewise a plan view with a sole face held generally in a horizontal posture, and 5(C) is a sectional view taken on line A-A of 5(A);

[0015]FIG. 6(A) is a perspective view showing a using state of the above iron club and FIG. 6(B) is an enlarged plan view of a grass relief groove portion; and

[0016] FIGS. 7(A)-7(C) are sectional views for explaining a using state of the iron club by way of separately and sequentially showing a swing stroke of the iron club.

DETAILED DESCRIPTION OF THE INVENTION

[0017] As shown in FIGS. 1 to 5, a single or plural grass relief grooves are formed in a leading edge portion zone 4 of an iron club head 1.

[0018] In other words, a single or plural grass relief grooves 5 are formed in a leading edge portion zone 4 of a club head 1 such that the grass relief groove 5 is open at a leading edge 4 a of the leading edge portion zone 4 and released at a surface 4 b on the side of the striking face 2 of the leading edge portion zone 4 and at a surface 4 c on the side of a sole face 3 of the leading edge portion zone 4.

[0019] The grass relief groove 5 is terminated in length not reaching at least a sweet spot region of the striking face 2.

[0020] A plurality of ball spinning grooves 9 generally parallel to the leading edge 4 a are formed in juxtaposed relation in the striking face 2 of the club head 1 in the iron club. Those ball spinning grooves 9 are for applying a reverse rotation to a golf ball. Preferably, the grass relief groove 5 does not reach in length the lowermost end ball spinning groove 9 a. In other words, the grass relief groove 5 is terminated in length just reaching the ball spinning groove 9 a. Otherwise, the grass relief groove 5 is terminated in length reaching two or three lower end ball spinning grooves 9 of all the ball spinning grooves 9. At any rate, it is preferable that the grass relief groove 5 is terminated in length not reaching the sweet spot.

[0021] In the illustrated examples, inner depths 5 b of the grass relief grooves 5 are arranged in juxtaposed relation in the leading edge portion zone 4 between the lowermost end ball spinning groove 9 a and the leading edge 4 a.

[0022] The grass relief groove 5 is a means for reducing grass resistance at the time of shot, especially grass resistance at the time of shot in the rough or soil resistance at the time of duffing and bunker shot by relieving grass 6 or soil into the grass relief groove 5. The number of the grass relief grooves 5 is determined by selecting the dimension and shape of the opening portion 6 a in accordance with a loft angle of the striking face 2 and the club number.

[0023] As one preferred example, a plurality of grass relief grooves 5 are formed in juxtaposed relation in the leading edge portion zone 4, in other words, from one end over to the other end of the leading edge portion zone 4 and an edge piece 8 is formed between every adjacent grass relief grooves 5. In other words, a plurality of edge pieces 8 are arranged in juxtaposed relation in the leading edge portion zone 4 and the grass relieve groove 5 is formed between every adjacent edge pieces 8.

[0024] As one specific example, as shown in FIG. 1 and others, the grass relief grooves 5 are spacedly formed in juxtaposed relation in the leading edge portion zone 4, in other words, along the leading edge 4 a and the rectangular edge piece 8 is formed between every adjacent grass relief grooves 5. Each rectangular edge piece 8 has a top side 8 a of a predetermined width which is formed on a distal end of the rectangular edge piece 8.

[0025] At the time of shot, a part of the grass 6 or soil is in abutment with the top side 8 a of the rectangular edge piece 8 and the remaining part is relieved into the relief groove 5.

[0026] As another specific example, as shown in FIG. 5, the grass relief grooves 5 and edge pieces 8 are sinusoidally formed in juxtaposed relation in the leading edge portion zone 4, in other words, along the leading edge 4 a. The grass relief groove 5 has an arc-like recessed configuration. Likewise, the edge piece 8 exhibits an arc-like protrusion configuration. The grass relief groove 5 has a form in which the width is gradually reduced from the opening portion 5 a towards the inner depth 5 b of the groove 5.

[0027] As one preferred example, the grass relief groove 5 has a form which is open at the opening portion 5 a and gradually converged towards the inner depth 5 b of the groove 5. In other words, it has a form which is gradually enlarged from the inner depth 5 b of the groove 5 towards the opening portion 5 a. That is to say, the grass relief groove 5 has a groove form having a generally V-shaped configuration as shown in FIGS. 1 and 5 which is open at the opening portion 5 a and gradually contracted at the inner depth 5 a of the groove 5.

[0028] The grass 6 is introduced from the enlarged (or dilated) opening portion 5 a of the grass relief groove 5 and converged towards the contracted inner depth 5 b of the groove 5. In doing so, a swing stroke is guided.

[0029] The grass relief groove 5 may take any one or any combination of V-shape, rectangular shape, arc-shape, trapezoidal shape and the like in accordance with necessity. The V-shape herein used includes a U-shape.

[0030] As shown in FIG. 6, at the time of shot, the grass relief grooves 5 allow that portion of grass corresponding to the grass relief grooves 5 to relieve therein and the golf ball 7 is caught at the striking face 2. In doing so, grass resistance at the time of shot is reduced and swaying of the club head 1 can be prevented more effectively. The follow-through of swing of the club head 1 can be conducted in a satisfactory manner and the golf ball 7 can be traveled on a right trajectory.

[0031] As one embodiment, a cutter 5 c for cutting the grass introduced into each grass relieve groove 5 is formed by a wall which defines the grass relief groove 5. The cutter 5 c together with the grass relieve groove 5 cut a part of most part of the grass 6 introduced into the grass relief groove 5 and the golf ball 7 is caught at the striking face 2. This can improve the reduction effect of the grass resistance and grass entangle at the time of shot. And swaying of the club head 1 can be prevented more effectively.

[0032] The grass 6 is introduced into each V-shaped grass relief groove 5 from the enlarged opening portion 5 a and converged towards the contracted inner depth 5 b of the groove 5. Owing to this arrangement, the grass cutting effect by the grass cutter 5 c is more improved.

[0033] FIGS. 1(A) to 1(D) show an example in which a groove edge portion facing the surface 4 b on the side of the striking face of the leading edge portion zone 4 and a groove edge portion facing a surface 4 c on the side of the sole face are used at the cutters 5 c.

[0034] As another example, as shown in FIGS. 2(A) to 2(C), a grass relief inclination surface 5 d, which is inclined downward towards the grass relieve groove 5, is formed on a peripheral edge of the surface 4 c on the side of the sole face of the leading edge portion zone 4 of the V-shaped grass relief groove 5, for example, peripheral edge of the surface 4 c on the side of the sole face of the leading edge portion zone 4 of the inner depth 5 b of the grass relief groove 5. By forming the grass relief inclination surface 5 d, a generally V-shaped grass guide groove 5 f is formed along the grass relief inclination surface 5 d and a grass cutter 5 c is formed on an end portion of the grass relief inclination surface 5 d.

[0035] It is preferred that the grass relief inclination surface 5 d and the grass guide groove 5 f are designed to be relatively long so that they have a V-shaped configuration in plan view. For example, the length of the grass relief inclination surface 5 d and the grass guide groove 5 f is once or twice as long as the depth of the grass relief groove 5 or more. They are designed to have a V-shaped configuration.

[0036] The grass relief inclination surface 5 d and the grass guide groove 5 f serve to effectively relieve the grass received into the grass relief groove 5 and fallen to the sole face 3 side, to reduce the follow-through swinging power and guide the follow-through swinging direction, and to prevent the striking face 2 to be deformed in angle.

[0037] As still another example, as shown in FIGS. 3(A) to 3(C), a grass relief inclination surface 5 e, which is inclined downward towards the grass relieve groove 5, is formed on a peripheral edge of the surface 4 b on the side of the striking face of the leading edge portion zone 4 of the V-shaped grass relief groove 5, for example, peripheral edge of the surface 4 b on the side of the striking face of the leading edge portion zone 4 of the inner depth 5 b of the grass relief groove 5, and a grass cutter 5 c is formed on an end portion of the inclination surface 5 e.

[0038] As still another example, as shown in FIGS. 4(A) to 4(C), a generally V-shaped short grass relief inclination surface 5 e, which is inclined downward towards the grass relieve groove 5, is formed on a peripheral edge of the surface 4 b on the side of the striking face of the leading edge portion zone 4 of the V-shaped grass relief groove 5, for example, peripheral edge of the surface 4 b on the side of the striking face of the leading edge portion zone 4 of the inner depth 5 b of the grass relief groove 5. Moreover, a generally V-shaped long grass relief inclination surface 5 b like the one shown in FIG. 2, which is inclined downward towards the grass relief groove 5 and a grass guide groove 5 f is formed on a peripheral edge of the surface 4 c on the side of the sole face of the leading edge portion zone 4 of the V-shaped grass relief groove 5, for example, peripheral edge of the surface 4 c on the side of the sole of the leading edge portion zone 4 of the inner depth 5 b of the grass relief groove 5. And a grass cutter 5 c is formed on each end portion of the inclination surfaces 5 d, 5 e.

[0039] Any example of FIGS. 3 and 4 includes a case which is further provided with a grass cutter 5 c formed by the V-shaped edge portion of the grass relief groove 5 as described with reference to FIG. 2.

[0040] The grass relief inclination surface 5 e is terminated in length, not reaching at least the sweet spot region of the striking face 2.

[0041] As one preferred example, the grass relief inclination surface 5 e is terminated in length, not reaching the ball spinning groove 9 a located at the lowermost end of the grass relief inclination surface 5 e, in other words, ball spinning groove 9 a located nearest to the leading edge 4 a, or just reaching the ball spinning groove 9 a. Otherwise, the grass relief inclination surface 5 e is terminated in length, just reaching approximately two to four ball spinning grooves 9 formed in a lower end of the ball spinning groove 9. At any rate, they are terminated in length, not reaching the sweet spot.

[0042] In the illustrated example, the end portions of the grass relief inclination surfaces 5 e are arranged in juxtaposed relation in the leading edge portion zone 4 between the lowermost end ball spinning groove 9 a and the leading edge 4 a.

[0043] The grass relief inclination surface 5 d and the grass guide groove 5 f of FIGS. 2 and 4 are terminated in length, not reaching the rear edge 10 of the sole face 3. Preferably, they are designed to be about twice to three times as long as the grass relief inclination surface 5 e. At any rate, they are preferably designed to have a length not reaching the sweet spot.

[0044] It should be noted, however, the present invention does not exclude the case wherein the grass relief inclination surface 5 d and the grass guide groove 5 f are designed to have a length, reaching the rear edge 10.

[0045] As shown in FIG. 7, the club head 1 shown in each of the above examples is fully swung (follow-through swing) on the trajectory R and brought into a place a little before the golf ball 7 as shown in FIG. 7(A). At that time, a rough grass 6 is interposed between the golf ball 7 and the leading edge 4 a of the club head 1. Reference character G denotes the ground.

[0046] When the swinging stroke is further progressed, as shown in FIG. 7(B), the grass 6 is allowed to relieve into the relief groove 5. While cutting a part of the grass 6 by the grass cutter 5 c, a lower face of the golf ball 7 is caught by the surface 4 b on the side of the striking face of the leading edge portion zone 4. Then, while throwing away upward the cut grass 6 as shown in FIG. 7(C), the golf ball 7 is caught by the nearby area of the sweet spot of the striking face 2 and caused to travel in the right direction.

[0047] In FIG. 7(B), the uncut and fallen grass 6 is guided by the grass relief inclination surface 5 d and the grass guide groove 5 f and in the meantime, the club head 1 is fully swung.

[0048] According to the present invention, grass resistance at the time of shot can be reduced extensively, follow-through of swing of a club head can easily be conducted in the rough even by beginners and powerless golfers, poor shot (miss a shot) such as chip and shank can effectively be eliminated, and safety is ensured by solving the problem of accident resulting in injury and death by shank, etc.

[0049] Moreover, according to the present invention, even if a duffing occurs, by reducing the ground resistance by means of allowing a part of the soil into the grass relief groove, the leading edge portion eaten into the ground can be brought out smoothly. In doing so, poor shot (miss a shot) caused by duffing can be minimized. 

What is claimed is:
 1. A structure of a head in an iron club for golf comprising a club head having a striking face and a sole face, wherein a grass relief groove is formed in a leading edge portion zone such that said grass relief groove is open at a leading edge and released at a surface on the side of said striking face of said leading edge portion zone and at a surface on the side of said sole face of said leading edge portion zone.
 2. A structure of a head in an iron club for golf comprising a club head having a striking face and a sole face, wherein a grass relief groove is formed in a leading edge portion zone of a club head such that said grass relief groove is open at a leading edge and released at a surface on the side of said striking face of said leading edge portion zone and at a surface on the side of said sole face of said leading edge portion zone, and a grass cutter for cutting grass introduced into said grass relief groove is formed with a wall for defining said glass relief groove. 